I have a 91 Z28, 305 auto. I just swapped in a set of 3.73's and need to recalibrate my speedo for cheap.

I am going to see if this works:

http://webpages.acs.ttu.edu/chdarby/DRAC.htm

I was just wondering if anyone has ever heard of this. I see/understand how it works and am very confident it does, but just wanted to know if there are any warnings...

One problem though, the chart he has only goes up to .98877, and the value for my setup (3.73s & 235/55/16's) is 1.02xxxx

I would be happy with it being that close but is there a better way for the same cost?

My stock ones were 2.73's, which would put the value at around .73 or so, I dont know because I havent checked the stock tire sizes...I bought the car with aftermarket rims and tires.

Basically I just wanted to ask if this guys calulations are correct.

I came up with 1.02 for my car so I would switch on #1 and #7 and switch all the others off.

Am I forgetting anything?

thanks a BUNCH

-Chris

EDIT: I found this after posting: it has the settings for my value(1.02)

http://www.pswired.com/misc/pacaudio/drac2.pdf

looks promising....